I have been using SimpleMathJax 0.3 on MW-1.23 where there was a context menu for the MathJax formulae with entries like "Show Math As ...", "Math Settings" etc. Now with version 0.7.3 on MW-1.31 I do not see this anymore and cannot find any way to enable it. Is there something I am missing or has this feature been dropped?
Topic on Extension talk:SimpleMathJax/Flow
Now, the context menu is supported by default. It can also be set with $wgSmjEnableMenu. Try version 0.8.1.